Serotonin in Alcoholism
|First Submitted Date||February 28, 2001|
|First Posted Date||March 1, 2001|
|Last Update Posted Date||March 4, 2008|
|Start Date||February 2001|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures||Not Provided|
|Original Primary Outcome Measures||Not Provided|
|Change History||Complete list of historical versions of study NCT00011752 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures||Not Provided|
|Original Secondary Outcome Measures||Not Provided|
|Current Other Outcome Measures||Not Provided|
|Original Other Outcome Measures||Not Provided|
|Brief Title||Serotonin in Alcoholism|
|Official Title||Effects of Acute Plasma Tryptophan Depletion on Serotonin Receptor Occupancy and Binding Affinity Using PET in Healthy and Alcoholic Human Subjects|
This study uses positron emission tomography (PET) scanning to study how serotonin works in alcoholics. Serotonin is a chemical that allows brain cells to communicate. There is evidence that people with alcoholism have altered serotonin; their brains begin to make and break down serotonin more slowly than people who do not drink. PET scans use radioactive substances injected into the body. A special camera detects the radiation emitted by the radioactive fluid and a computer processes the radioactivity into images of the brain, which show the activity of brain chemicals like serotonin.
People with alcohol dependency may participate in this study. Candidates are screened with a medical history, including questions about alcohol and drug use, physical examination, blood tests, breath alcohol tests, electrocardiogram (ECG), urine test for illicit drugs and, for women, a pregnancy test, and a stool test for hidden blood. They also undergo magnetic resonance imaging (MRI) scan of the brain and complete questionnaires on their alcohol and drug history.
Participants undergo the following tests and procedures:
Patients are admitted to the intensive care unit for the lumbar puncture and arterial line procedures. After these procedures are complete, the patient is transferred by stretcher to the PET suite for scanning. During the two scans, blood samples are drawn from the artery and a small amount of CSF is collected each hour of the study. Each PET scanning session lasts about 3 hours. The study lasts 36 hours, during which time the subject remains in bed.
This research concerns the study of serotonin (5-HT) synthesis, metabolism (turnover), and release. We hypothesize that neuronal 5-HT turnover and release is altered in alcoholic individuals, and that this plays a role in alcohol seeking behavior. We wish to determine the following:
To investigate the underlying biochemistry of 5-HT neurometabolism, we will use two experimental strategies, Acute Tryptophan (TRP) Depletion (ATD) and positron emission tomography (PET) imaging, to investigate 5-HT neurochemistry. We will deplete plasma TRP, using ATD, while simultaneously collecting CSF 5-HIAA and performing intermittent plasma sampling via indwelling catheters. TRP is the amino acid (AA) precursor needed for 5-HT synthesis. 5-HIAA is the principal metabolite of 5-HT. It is a neurochemical marker of neuronal 5-HT metabolism. PET will allow indirect measurements of synaptic 5-HT concentration by measuring binding of [(18)F]-FCWAY, a 5-HT (1A)-receptor antagonist. rCBF will be measured with [(15)O]-water imaging. Studies will be performed before and after ATD. Individuals will be genotyped for the 5-HT transporter (5-HTT). Plasma TRP and Large Neutral Amino Acids (LNAAs), and CSF TRP and 5-HIAA concentrations will be measured using High Performance Liquid Chromatography (HPLC).
|Study Design||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Study Groups/Cohorts||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Estimated Completion Date||September 2005|
|Primary Completion Date||Not Provided|
Patients who have met standard DSM-IV R criteria for alcohol dependence and limited number psychiatric conditions that characterize patients with mood disorders that are difficult to separate from their alcohol use.
Age and sex matched healthy research comparison participants. The healthy research comparison participants need to be free of medical, neurological, and psychiatric illness. They should be medication free at the time of study. They should not meet criteria for alcohol or substance abuse, and cannot have a history of such use placing them in questionable diagnostic categories.
The age range of study participants is from 18 to 65 years.
Subjects from a diverse racial, ethnic, and gender backgrounds will be included in the study. This is because alcohol dependence manifests itself differently in different racial and gender groups.
Significant medical problems, e.g., active GI bleed, cancer, active hepatitis B infection or other medical diseases associated with liver pathology other than hepatitis C or alcoholism (e.g. Hemochromatosis).
Other psychiatric illnesses represent diagnostic categories not eligible for this study. Examples of these include Major Depressive Disorder, Bipolar Disorder, acute or chronic psychotic illness (e.g. Schizophrenia), and Substance Induced Mood Disorders (i.e. secondary to illicit drug dependence; e.g. heroin, cocaine, crack, PCP, and other illicit substances that affect brain function).
Intravenous drug use within the past three months.
Drug or medication use, strongly associated with liver dysfunction, CNS effects, or impaired GI absorption (e.g. high doses of acetaminophen, neuroleptic medications, and narcotic medications).
History of significant GI surgery (e.g. Roux en Y procedure, partial gastrectomy), which would interfere with normal GI absorption of dietary constituents.
Coagulation defects or lack of dual circulation.
Severe iron deficiency anemia, marked low hematocrit or hemoglobin.
Pregnancy: a positive pregnancy test will preclude further participation in this protocol.
Inability to give a clinical history or informed consent.
Positive human immunodeficiency virus (HIV) diagnosis: patients with positive HIV status/AIDS will be excluded form the study.
Individuals may be excluded from entering the study at the discretion of the Principal Investigator, Dr. Williams, based on his clinical judgment.
Participants who have had an adverse reaction that mimics any of the anticipated adverse events in response to a pharmacological challenge study or to a prescribed medication.
|Ages||Child, Adult, Senior|
|Accepts Healthy Volunteers||Yes|
|Contacts||Contact information is only displayed when the study is recruiting subjects|
|Listed Location Countries||United States|
|Removed Location Countries|
|Other Study ID Numbers||010090
|Has Data Monitoring Committee||Not Provided|
|U.S. FDA-regulated Product||Not Provided|
|IPD Sharing Statement||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor||National Institute on Alcohol Abuse and Alcoholism (NIAAA)|
|PRS Account||National Institutes of Health Clinical Center (CC)|
|Verification Date||September 2005|